FALLUJAH, IRAQ
— US Marine commanders battling insurgents in Iraq say the destruction of a large weapons cache Tuesday night - and further airstrikes Wednesday - reinforces their belief that putting off an all-out assault on Fallujah is, for now, paying dividends.

Frontline Marine units encircling the city spotted two trucks loaded with ammunition late Tuesday and called in AC-130 Specter gunships. Striking those targets and nearby houses - one of which also proved to have a substantial stock of ordnance - set off dramatic secondary explosions.

Iraqi sheikhs from around Iraq are reportedly converging on Fallujah to mediate, and Iraqi police bolstered their presence on the street Wednesday in anticipation of joint US-Iraqi patrols supposed to begin later this week.

Support among officers here for a non-assault solution grows as the destruction of the weapons cache - combined with targeted US strikes that have wiped out several groups of insurgents is achieved while incurring few US or Iraqi civilian casualties.

"The military solution is always there, but we have a lot of different arrows in our quiver," says Col. John Coleman, chief of staff of the 1st Marine Expeditionary Force that controls western Iraq. "The key is to decide which one to notch, and when." Shelling and fierce exchanges of gunfire broke out again in mid-afternoon Wednesday in Fallujah. Jet aircraft, helicopters and heavy planes joined the action. A US television pool reporter embedded with the Marines said that a heavy assault had been launched in support of a unit which attempted to take a rail station from guerrillas who have controlled the town for over three weeks.

A "Cease-fire" has technically been in place for two weeks, but the word doesn't seem to apply to the military back and forth of recent days. Besides the fighting, insurgents are regrouping and reloading, and tens of thousands of civilians hunker down in Fallujah in anticipation of a US siege. But the military says the current strategy is bearing fruit.

"We are beginning to see signs that this is working," says Colonel Coleman. "More and more, people are beginning to come to us. It's a subtle change, but that shift is beginning to happen."

In the past, such signals have included Iraqis coming to US forces with intelligence about insurgents or weapons caches, though Coleman would not be drawn on what specific signals the Marine command has seen. Crucial to building trust, he says, is evidence seen by the people of Fallujah that US firepower is aimed only at insurgents - and that it's being effective.

"We are trying to be the wedge between people who don't want to see this violence, and their intimidators," Coleman says. "If we can remove the intimidators, then people should cease being intimidated."

A powerful insurgent attack Monday morning - which Marines said was the most well-orchestrated and forceful that they have seen in weeks - appeared to bolster arguments that delaying any offensive was dangerous.

US forces aimed to keep pressure on the insurgents, using a psychological operations leaflet drop on the city before the air strikes began. "Surrender, you are surrounded," the leaflets said. "If you are a terrorist, beware, because your last day was Wednesday. In order to spare your life end your actions and surrender to coalition forces now. We are coming to arrest you."

The moderate tone at the command level here is in stark contrast to the ultimatums given to insurgents last week to disarm or face a full military offensive, which stemmed from uncompromising rhetoric in Washington over the Fallujah standoff.

Brig. Gen. Mark Kimmitt, the US military spokesman in Baghdad, said Tuesday that it could take between six and eight weeks to take full control of Fallujah, where four US private security guards were killed on March 31. US officials say they continue to support negotiations between Iraqi civilian leaders and insurgents in Fallujah. But skepticism is growing. "They continue to tell us that they represent the people. But they don't deliver," said General Kimmitt Wednesday.

Kimmitt, told ABC television shortly before the new outbreak of fighting that he still hoped for a deal. "We are going to continue to push the political track as far as it is going to take us and if it does not take us far enough, we are prepared to use military means," he said. "If they have to take this to a fight, that's going to be a one-way fight."

The Pentagon, too, is voicing second thoughts, as it contemplates the political and military ramifications of a strike, which could galvanize anti-American views in Iraq on the eve of the June 30 handover to Iraqi sovereignty. Also on the military agenda: the face-off in Najaf with militant cleric Moqtada al-Sadr and his Mahdi militia.

While few here hold out much hope for a diplomatic breakthrough, Secretary of Defense Donald Rumsfeld said Tuesday that talks are "worth a try."

"I think that realistically if you've got some very tough people in a city that are terrorists ... that you have to expect that they're not going to be terribly cooperative," he said. "Now, does that mean that something can't be worked out? No."